CNN  — 

France is in the sweaty grasp of a hot weather phenomenon known as la canicule – and forecasters are running out of ways to describe both its immediate danger and ominous long-term significance.

Last week, meteorologist Ruben Hallali found an apt metaphor in this image: a weather forecast model for Thursday, June 27, whose patterns of temperatures across France just happened to create the image of a screaming skull.

Naturally he tweeted it paired with Edvard Munch’s 1893 painting, “The Scream”.

The map was first published on June 20 on Météociel, a French site that automatically generates weather pattern visualizations based on data from various forecasting models. Météociel spokesperson Sylvain Dupont told CNN that this particular map had been generated from real data created by the US predictive Global Forecast System.

“By chance, it just happened to be possible to imagine a special form of a skull in this map,” he said, emphasizing the randomness of the apparition. “There are so many maps created on our site for each updated forecast that it is statistically possible for some to look like something.”

The map was nevertheless “remarkable,” Dupont said, because it showed air temperatures of 26 to 28 degrees Celsius (79-82 Fahrenheit) across nearly all of France, an uncommon high for this time of year. “It represents well the current canicule,” he added. CNN Weather now predicts a high of 34 degrees Celsius (93 Fahrenheit) for Paris on Thursday.

According to French national meteorological service Météo-France, canicules can be distinguished from ordinary heatwaves by their unrelenting intensity, with sweltering nights as well as days. They generally occur late in the summer, between July 15 and August 15.

Climate change could explain the high temperatures striking Europe unusually early this year, as CNN previously reported. On Wednesday, a German town broke a record with 38.6 degrees Celsius (101.5 Fahrenheit) – the hottest temperature ever recorded in the country. Multiple sites in France also broke heat records.

Global warming is expected to increase the frequency and intensity of dangerous canicules in the future, warns Météo-France. Extreme heat has killed before in Europe, and in 2003 scarred the whole of France with the deaths of more than 14,000 mostly elderly people.

“Canicule” itself, derived from the Latin word for dog, is a term loaded with foreboding. Just like Italy’s canicola and the US and UK’s “dog days of summer,” the term refers to the time of year when the star Sirius, also known as the “dog star” or Orion’s Hound, rises with the sun – a period that the ancients associated with both heat and chaos on Earth.

In the Iliad, Homer describes “the star which men call Orion’s Hound” as the brightest of all – and yet one which “bodes ill for mortals, for he brings fire and fever in his train.”